I am building an HBR-11 receiver as originally featured in April 1963 QST magazine.

The BFO is a 100 kHz (I believe Hartley) oscillator and uses a tapped coil.

I had to wind my own BFO coil on a used slug-tuned form.

The oscillator is operating and can achieve 100 kHz but .. the bottom of the output sin wave is flattened. It sort of looks as if the tube isn’t biased in the center of it’s load line.

Can anyone tell me how critical this is? I would think that this could cause some non-linear distortion in the audio, but the radio is just receiving voice transmission, so perhaps it’s OK to leave it as is?

The BFO signal gets injected into a 6BY6 product detector, should that information be of any significance.

When I used to build my homebrew receivers I would first lay out all the major parts and mount them. That would be the VFO capacitor, bandswitch, tube sockets, and transformers including IF transformers. I would start wiring at the power supply and then audio and work backwards.

I was asking you about your receiver with the double tuned input system. The one where you had two peaks on the input tuning.

The last thing that I did with that project was to laser engrave a front panel, so at least it looks really nice now :-)

I was getting frustrated with the double peaks situation and wasn't making much headway. Then, I read about the HBR receivers in QST magazine and got the bug to build one of those, so my Simple-X receiver is rear "burner-ed" for the moment.

When I get frustrated with my HBR-11, I'll come back to the Simple-X with vigor renewed and try again :-)

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